This is a barebones, incomplete idea - a stub article, as it were, please expand on it with your own thoughts.
The Houses of Parliament meet in a crumbling, grand complex of palaces and religious symbolism, topped off with an iconic clock tower. Will this always be the way it is? The buildings in question are unsuitable for the sheer numbers trying to use them these days, and rather than taking the Conservative approach of reducing the number of MPs in spite of the increased population, we need to look at doing something else entirely.
What makes a Capital City so important? Why is London (or Westminster) the place where all the decisions are made? Does it not seem odd that a dank, marshy estuarine corner of these isles has been the centre of political gravity within them for the last two thousand years, more or less? Setting aside the fact that eight million or so people occupy the sprawl of the 'Greater' London area as being mainly a symptom after the fact, ought we not consider that we now live in a much more connected society? If we want true democracy, ought we not allow the decisions to be made in the places they affect the most? BBC's 'Question Time' is capable of bringing the debate to the people both physically and on the TV, and utilises Twitter to at least superficially involve the viewers. Whilst this does not go far enough, it is at least a step in the right direction. London was a city that grew largely by the arrival of trade by sea. Most of the docks there are long since shut now, and those that remain are largely for tourism or as the backyard ponds to the towers of the oligarchy. We have all moved on now, and sail different seas; trade comes in packets of data and physical location doesn't have quite the importance it used to for the ability to run the show.
I propose a policy that the Houses of Parliament are taken out of their current use altogether, but unlike Dawud Islam's suggestion that they should be replaced by some new structure in 'some central location', instead why can't we see parliament come to us? Granted, some towns lack the facilities for such large gatherings - so they'll finally get the investment in multi-use (and of course eco-friendly by design) larger exhibition, conference and community events spaces. But even if we just started by circulating around the ten biggest cities, it would be an improvement over the current London-centric parliamentary paradigm, which seems largely to be a by-product of the presence of the monarchy. You might also start to persuade the Scottish (and a lot of the rest of us) that the UK parliament isn't just concerned with Southern England's welfare. It would lead to more people from the 'provinces' getting interested in national level politics without having to travel to London all of the time and make a career out of it by getting a degree.
To make our political system truly participatory, we do of course need electoral reform too, and we need democracy via the internet to be the new normal. Referenda should be routinely available for voting online. We live in a country of 65 million people, and I bet near enough all of them have something to say at some point. So we need to break free of this entirely artificial notion that London is somehow a 'special case'.
We also need to break free of the notion that we can arbitrarily appoint a whole chamber of our parliament from people claimed to be 'special cases' based purely on them either being people who have scratched the right backs or are descendants of those who did. The House of Lords needs to be scrapped in its current form, and in its place I reckon we should put the House of Sortition, picked at random from the populace with very minimal requirements of eligibility. The Houses of Commons and Sortition could tour the country independently of one another, so that important political things are always going on in at least two parts of the country at once.